Lifestyle, Nutrition, and Colorectal Cancer

Although colorectal cancer is declining for many groups in the US, cases continue to rise in patients under the age of 50 years.¹ People under the age of 50 also tend to have more aggressive colorectal cancers, which is a prime example of a condition that can be prevented with lifestyle interventions.² Screening for colorectal cancer begins at 50 years of age, and early detection is highly correlated with decreased mortality.¹

This 2018 data line up with a study from 2017, which found a 22% increased rate of colon cancer in people under the age of 50, as well as an increased risk of death from colon cancer in this younger group.²

Many factors are likely to contribute, including:

• Alcohol use: Moderate and heavy alcohol use raises the risk of colorectal cancer,^3,4 and alcohol use and binge drinking is soaring throughout the US, with significant increases in alcohol usage, high-risk drinking, and alcohol use disorder across most sociodemographic groups, with greater increases for most non-white populations.⁵
• Oral health: Although still emerging, research suggests poor oral health may raise the risk for colorectal cancer.⁶ A recent study links periodontal disease to increased risk of colorectal cancer.³ Estimates are that almost half of Americans have periodontal disease.^7,8 Risk of periodontal disease is much higher in lower-income groups.⁸ Periodontitis may be a risk factor for many cancers,^9,10 especially smoking-related cancers (note that this study found no correlation between periodontitis, nonsmokers, and colorectal cancer).¹⁰ Tooth loss has also been correlated with increased risk for colorectal cancer, possibly due to associated Fusobacteria.¹¹
• Processed meat consumption: Processed meat is known to have carcinogenic effects,¹² and the International Agency for Research on Cancer concludes that it contributes to colorectal cancer.¹³ Men consume more meat than women,¹⁴ which may play a role in their increased colorectal cancer risk. The highest meat consumption is among people aged 20 to 49, and over the last century, meat intake has gone up dramatically in the US.¹⁵

Recommendations for at-risk patients

Many of the recommendations for preventing colorectal cancer are core tenets of Functional Medicine. For instance, high fruit and vegetable consumption appears to be protective.⁴ Research supports the benefits of a high-fiber, low-meat diet to prevent colorectal cancer.¹⁶ Diets with lower overall nutrition are linked to many forms of cancer, including colorectal.¹⁷

In addition, consumption of green tea has strong research support as preventative for colorectal cancer, primarily in cohort and case-controlled studies in Asia and America.^18,19 This effect may be stronger in women.¹⁹